I re-installed these three libraries and then the login worked

So much for my assertion that there's "Nothing there that's going to cause any problems (except for speed of processing)". Perhaps, with pure perl, things are so slow that a timeout was occurring.

IIRC, the code that tries to load those modules goes something like:

use Math::BigInt lib => 'GMP Pari BitVector';
[download]

which tries to load the respective modules in that order. It's therefore unnecessary to install all three, as the first one that gets found is the one that will be used. If the first one that's specified is found, then there will be no warnings issued about the others if they are absent. (And, as already stated, if none are found, then the pure perl Math::BigInt is used.) GMP and Pari are significantly faster than BitVector, and therefore preferable.

How did you know the libraries?

I remember from a few years back that there were GMP, Pari and Bit::Vector plug-ins available for Math::BigInt. (Actually ... I don't see Math::BigInt::BitVector on CPAN any more. Was I right about it ?)

Cheers,
Rob